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Thermodynamic favorable CO2 conversion via vicinal diols and propargylic alcohols:A metal-free catalytic method

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Chinese Chemical Letters 2020年第2期31卷 341-344页

作者： Li-Hua Han Jing-Yuan Li qing-wen song Kan Zhang Qian-Xia Zhang Xiao-Fang Sun Ping Liu State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China

Organocatalysis represents a promising field in chemical fixation of ***,a facile metal-free strategy was reported for the one-pot preparation of cyclic carbonates and a-hydroxy ketones from vicinal diols,propargylic alcohols and *** scope of vicinal diols and propargylic alcohols was demonstrated to be efficient under the DBU-catalyzed conditions.A plausible mechanism was proposed,which included detailed main and side reactions under the metal-free conditions.

关键词： Carbon dioxide utilization Cascade reaction Chemicals Metal-free catalysis Synthetic methods

Hysteresis effect in current–voltage characteristics of Ni/n-type 4H-SiC Schottky structure

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Chinese Physics B 2019年第11期28卷 316-321页

作者： Hao Yuan qing-wen song Chao Han Xiao-Yan Tang Xiao-Ning He Yu-Ming Zhang Yi-Men Zhang School of Microelectronics Xidian UniversityXi’an 710071China

Hysteresis current–voltage(Ⅰ–Ⅴ) characteristics are often observed in a highly non-ideal(n > 2) as-deposited nickel(Ni)/4 H-SiC Schottky contact. However, we find that this kind of hysteresis effect also exists in an as-deposited Ni/n-type4 H-SiC Schottky structure even if the ideality factor(n) is less than 1.2. The hysteresis Ⅰ–Ⅴ characteristics is studied in detail in this paper by using the various measurements including the hysteresis Ⅰ–Ⅴ, sequentialⅠ–Ⅴ sweeping, cycle Ⅰ–Ⅴ,constant reverse voltage stress(CRVS). The results show that the hysteresis Ⅰ–Ⅴ characteristics are strongly dependent on the sweeping voltage and post-deposition annealing(PDA). The high temperature PDA(800℃) can completely eliminate this hysteresis. Meanwhile, the magnitude of the hysteresis effect is shown to decrease in the sequential Ⅰ–Ⅴ sweeping measurement, which is attributed to the fact that the electrons tunnel from the 4 H-SiC to the localized states at the Ni/ntype 4 H-SiC interface. It is found that the application of the reverse bias stress has little effect on the emission of those trapped electrons. And a fraction of the trapped electrons will be gradually released with the time under the condition of air and with no bias. The possible physical charging mechanism of the interface traps is discussed on the basis of the experimental findings.

关键词： 4H-SiC Schottky hysteresis Ⅰ–Ⅴ Schottky barrier height

Lateral depletion-mode 4H-SiC n-channel junction field-effect transistors operational at 400℃

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Chinese Physics B 2021年第2期30卷 567-572页

作者： Si-Cheng Liu Xiao-Yan Tang qing-wen song Hao Yuan Yi-Meng Zhang Yi-Men Zhang Yu-Ming Zhang Key Laboratory of Wide Band Gap Semiconductor Materials and Devices Xidian UniversityXi'an 710071China School of Microelectronics Xidian UniversityXi'an 710071China XiDian-WuHu Research Institute WuHu 241000China

This paper presents the development of lateral depletion-mode n-channel 4 H-SiC junction field-effect transistors(LJFETs)using double-mesa process toward high-temperature integrated circuit(IC)*** room temperature,the fabricated LJFETs show a drain-to-source saturation current of 23.03μA/μm,which corresponds to a current density of 7678 A/cm^(2).The gate-to-source parasitic resistance of 17.56 kΩ·μm is reduced to contribute only 13.49%of the on-resistance of 130.15 kΩ·μm,which helps to improve the transconductance up to 8.61μS/μ*** temperature characteristics of LJFETs were performed from room temperature to 400℃.At temperatures up to 400℃in air,it is observed that the fabricated LJFETs still show normally-on operating *** drain-to-source saturation current,transconductance and intrinsic gain at 400℃are 7.47μA/μm,2.35μS/μm and 41.35,*** results show significant improvement over state-of-the-art and make them attractive for high-temperature IC applications.

关键词： junction field-effect transistors high temperature 4H-SiC depletion-mode

A Low Complexity VCS Method for PAPR Reduction in Multicarrier Code Division Multiple Access

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Journal of Electronic Science and Technology of China 2007年第2期5卷 102-106页

作者： Si-Si Liu Yue Xiao qing-song wen Shao-Qian Li National Key Lab of Communications University of Electronic Science and Technology of China （UESTC） Chengdu 610054 China

This paper investigates a peak to average power ratio （PAPR） reduction method in multicarrier code division multiple access （MC-CDMA） system. Variable code sets （VCS）, a spreading codes selection scheme, can improve the PAPR property of the MC-CDMA signals, but this technique requires an exhaustive search over the combinations of spreading code sets. It is observed that when the number of active users increases, the search complexity will increase exponentially. Based on this fact, we propose a low complexity VCS （LC-VCS） method to reduce the computational complexity. The basic idea of LC-VCS is to derive new signals using the relationship between candidature signals. Simulation results show that the proposed approach can reduce PAPR with lower comtational pucomplexity. In addition, it can be blindly received without any side information.

关键词： Low complexity variable code sets,multicarrier code division multiple access (MC-CDMA),peak to average power ratio variable code sets.

Effects of pioglitazone on serum leptin and adiponectin in polycystic ovary syndrome patients with insulin resistance

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Journal of Pharmaceutical Analysis 2010年第1期22卷 59-62页

作者： qing song,wen-Li Gou,Xiu-Ju Ding Department of Obstetrics & Gynecology,the First Affiliated Hospital,Medical School of Xi’an Jiaotong University,Xi’an 710061,China Department of Obstetrics and Gynecology First Affiliated Hospital Medical School of Xi'an Jiaotong University Xi'an 710061 China

Objective To investigate the effects of pioglitazone on serum leptin and adiponectin in polycystic ovary syndrome(PCOS)patients with insulin resistance(IR).Methods Thirty-five PCOS patients with IR were treated with pioglitazone 15mg/d for 12 *** results of ovulation induction were *** changes of fasting plasma glucose(FPG),fasting serum insulin(FINS),serum levels of leptin,adiponectin,follicle-stimulating hormone(FSH),luteinizing hormone(LH),testosterone(T)and blood fat were examined at the baseline and after the therapy by enzyme-linked immunosorbent assay(ELISA)and radioimmunoassay(RIA).Results After the treatment,the rate of ovulation per cycle was improved in 31(88.5%)out of the 35 *** treatment,the level of serum leptin was decreased(P0.05).The levels of LH,T,FINS,Homa-IR,total cholesterol,triglyceride and low density lipoprotein-cholesterol were significantly decreased(P0.05).Conclusion Pioglitazone treatment can effectively improve PCOS with IR patients’ clinical syndromes,insulin sensitivity,glucose and lipid metabolism at least partly through improving the profiles of leptin and adiponectin.

关键词： pioglitazone polycystic ovarian syndrome insulin resistance leptin adiponectin

化脓性阑尾炎并发糖尿病患者的微创手术效果研究

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中国内镜杂志 2015年第12期21卷 1298-1301页

作者：李岩松赵庆楠宋文卿黑龙江省大庆龙南医院普外科黑龙江大庆163453

目的分析腹腔镜阑尾切除术对化脓性阑尾炎并发2型糖尿病患者的临床效果。方法选取2013年1月-2014年12月于该院手术治疗的68例急性化脓性阑尾炎合并2型糖尿病患者为研究对象,采用随机数字表法将患者随机分为腹腔镜组和开腹组,每组34例。... 详细信息

目的分析腹腔镜阑尾切除术对化脓性阑尾炎并发2型糖尿病患者的临床效果。方法选取2013年1月-2014年12月于该院手术治疗的68例急性化脓性阑尾炎合并2型糖尿病患者为研究对象,采用随机数字表法将患者随机分为腹腔镜组和开腹组,每组34例。比较两组患者的术中情况、术后康复情况及术前10 min(T1)、手术开始后30 min(T2)及手术结束后30 min(T3)的血糖、胰岛素及胰岛素抵抗指数的变化。结果腹腔镜组患者较开腹组手术时间短,手术切口小,术中出血量少,差异均有统计学意义(P0.05)。在T2时间点,开腹组患者的胰岛素、血糖及胰岛素抵抗指数分别为(17.6±1.4)m U/L、(9.8±1.3)mmol/L和(7.6±0.4),明显高于腹腔镜组的(15.2±0.9)m U/L、(8.7±1.4)mmol/L和(5.4±0.3)。结论采用腹腔镜阑尾切除术治疗急性化脓性阑尾炎合并2型糖尿病患者具有创伤小、恢复快、并发症少等优点,且对患者的血糖、胰岛素水平及胰岛素抵抗的影响小。

关键词：化脓性阑尾炎 2型糖尿病腹腔镜

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一元及多元信号分解发展历程与展望

自动化学报 2024年第1期50卷 1-20页

作者：陈启明文青松郎恂谢磊苏宏业浙江大学工业控制技术国家重点实验室杭州311100 阿里巴巴达摩院杭州310027 阿里巴巴达摩院美国西雅图98060 云南大学信息学院昆明650091

现实世界中,所获得的信号大部分都是非平稳和非线性的,将此类复杂信号分解为多个简单的子信号是重要的信号处理方法.1998年,提出希尔伯特–黄变换(Hilbert-Huang transform,HHT)以来,历经20余年的发展,信号分解已经成为信号处理领域相... 详细信息

现实世界中,所获得的信号大部分都是非平稳和非线性的,将此类复杂信号分解为多个简单的子信号是重要的信号处理方法.1998年,提出希尔伯特–黄变换(Hilbert-Huang transform,HHT)以来,历经20余年的发展,信号分解已经成为信号处理领域相对独立又具有创新性的重要内容.特别是近10年,多元/多变量/多通道信号分解理论方法方兴未艾,在诸多领域得到了成功应用,但目前尚未见到相关综述报道.为填补这个空缺,从单变量和多变量两个方面系统综述了国内/外学者对主要信号分解方法的研究现状,对这些方法的时频表达性能进行分析和比较,指出这些分解方法的优势和存在的问题.最后,对信号分解研究进行总结和展望.

关键词：信号分解时频分析希尔伯特–黄变换多元信号分解

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An efficient quantum proactive incremental learning algorithm

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 49-57页

作者： Lingxiao Li Jing Li Yanqi song Sujuan Qin Qiaoyan wen Fei Gao State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications School of Cyberspace Security Beijing University of Posts and Telecommunications

In scenarios where a large amount of data needs to be learned, incremental learning can make full use of old knowledge, significantly reduce the computational cost of the overall learning process, and maintain high performance. In this paper, taking the MaxCut problem as our example, we introduce the idea of incremental learning into quantum computing, and propose a Quantum Proactive Incremental Learning algorithm(QPIL). Instead of a one-off training of quantum circuit, QPIL contains a multi-phase training on gradually-increased subgraphs of all vertices, proactively reducing large-scale problems to smaller ones to solve in steps, providing an efficient solution for MaxCut. Specifically, some vertices and corresponding edges are randomly selected for training to obtain optimized parameters of the quantum circuit at first. Then, in each incremental phase, the remaining vertices and corresponding edges are gradually added and the parameters obtained from the previous phase are reused in the parameter initialization of the current phase. We perform experiments on 120 different small-scale graphs, and it shows that QPIL performs superior to prevalent quantum and classical baselines in terms of approximation ratio(AR), time cost, anti-forgetting, and solving stability. In particular, QPIL's AR surpasses 20% of mainstream quantum baselines, and the time cost is less than 1/5 of them. The idea of QPIL is expected to inspire efficient and high-quality solutions in large-scale Max Cut and other combinatorial optimization problems.

关键词： variational quantum algorithm incremental learning multi-phase training MaxCut quantum computing

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迁徙自由权探析

武汉大学学报（人文科学版） 2004年第5期57卷 573-577页

作者：问清泓问青松武汉科技大学文法与经济学院湖北武汉430081 武汉大学商学院湖北武汉430072

迁徙自由权是公民的基本权利之一,世界各国宪法和国际人权公约中都有关于迁徙自由权的规定。我国现行宪法没有规定迁徙自由权,但社会主义市场经济、我国户籍制度改革及履行国际义务等都需要恢复迁徙自由,因此,此立法具有重要意义与价值。

关键词：迁徙自由权公民权利宪法户籍制度定义立法工作国际人权公约